Add pyproject.toml and installation documentation (#8)

* Add pyproject.toml

* docs: Python installation documentation

Author: jjokella

docs/users_guide/README.md

@@ -19,3 +19,12 @@ generation and manipulation.
 - [create_ensemble_namelists.py](create_ensemble_namelists.md):
   Creates per-ensemble-member namelist files for eCLM-PDAF Data
   Assimilation experiments.
+
+## Installation
+
+From the repository root install the dependencies using the provided
+`pyproject.toml`:
+
+```bash
+pip install .
+```

pyproject.toml

@@ -0,0 +1,13 @@
+[project]
+name = "eCLM_namelist-generator"
+version = "0.1.0"
+description = "Scripts related to eCLM namelist files"
+readme = "README.md"
+requires-python = ">=3.11"
+dependencies = [
+    "f90nml>=1.4",
+    "lxml>=4.9",
+]
+
+[tool.setuptools]
+packages = []